Account Abstraction

How embarkAI uses ERC-4337 account abstraction for smart wallet functionality.

embarkAI smart wallets are built on the ERC-4337 Account Abstraction standard. Instead of relying on externally owned accounts (EOAs) controlled by a single private key, every embarkAI wallet is a smart contract with programmable transaction logic, gas sponsorship, and batched calls.

What is Account Abstraction?

Account Abstraction (AA) decouples transaction validation from Ethereum’s native protocol. With ERC-4337, smart contract accounts can define their own signature schemes, pay gas on behalf of users, and execute multiple operations atomically — all without changes to the consensus layer.

Key Concepts

Concept	Description
Smart Account	A smart contract that acts as a user’s wallet, with custom validation logic
UserOperation	A pseudo-transaction object that describes what the smart account should execute
EntryPoint	A singleton contract that validates and executes UserOperations on-chain
Bundler	An off-chain service that collects UserOperations and submits them to the EntryPoint
Paymaster	An optional contract that sponsors gas fees on behalf of the user

UserOperations Explained

A UserOperation replaces the traditional Ethereum transaction. Instead of signing a transaction directly, users sign a UserOperation that the EntryPoint contract processes.


// Sending a UserOperation with the EmbarkAI SDK
import { createServerWalletManager, MemoryKeyshareStorage } from '@embarkai/core'
 
const manager = createServerWalletManager({
  apiKey: process.env.EMBARK_API_KEY!,
  chainId: 994873017,
  storage: new MemoryKeyshareStorage(),
})
 
const wallet = await manager.getWallet('my-wallet')
 
// The SDK constructs, signs, and submits the UserOperation internally
const userOpHash = await wallet.sendUserOperation(
  '0xRecipientAddress',
  '1000000000000000000', // 1 LUMIA in wei
)

Behind the scenes, the SDK:

Constructs a UserOperation with the correct nonce, gas limits, and calldata
Signs the operation using the DKLS23 threshold signature protocol
Submits it to the Bundler
The Bundler validates and sends it to the EntryPoint contract on-chain

The EntryPoint Contract

The EntryPoint is a singleton contract deployed at a well-known address on every supported chain. It is responsible for:

Validating each UserOperation’s signature via the smart account’s validateUserOp method
Executing the call defined in the UserOperation
Handling gas payments — either from the smart account’s deposit or via a Paymaster
Emitting events that allow off-chain indexing of UserOperation results

embarkAI uses EntryPoint v0.7, which is automatically configured for all supported chains.

The Bundler

The Bundler is an off-chain service that aggregates UserOperations and submits them to the EntryPoint in a single on-chain transaction. embarkAI runs managed Bundler infrastructure so you do not need to operate your own.

The Bundler performs several checks before inclusion:

Validates the UserOperation signature
Simulates execution to ensure it will succeed
Estimates gas requirements
Submits the bundle to the blockchain

Paymaster: Gas Sponsorship

A Paymaster contract can pay gas fees on behalf of users, enabling gasless transactions. When a Paymaster is configured, users never need to hold native tokens to transact.


import { createServerWalletManager, MemoryKeyshareStorage } from '@embarkai/core'
 
const manager = createServerWalletManager({
  apiKey: process.env.EMBARK_API_KEY!,
  chainId: 994873017,
  storage: new MemoryKeyshareStorage(),
  paymasterAddress: '0x742d35Cc6634C0532925a3b844Bc454e4438f44e', // optional: your own paymaster instead of the default one
})

See the Paymaster documentation for details on configuring gas sponsorship.

Smart Account Lifecycle

embarkAI smart accounts follow a counterfactual deployment model:

1. Wallet Creation (Off-chain)

When you call createWallet(), the SDK runs the DKG protocol to generate a key pair and computes the counterfactual address — the deterministic address where the smart account will be deployed. No on-chain transaction occurs at this stage.

2. First Transaction (Deployment)

The first UserOperation sent from the wallet includes the factory and factoryData fields (ERC-4337 v0.7) that deploy the smart account contract. The EntryPoint uses the AA factory contract to deploy the account and then executes the operation — all in one transaction.

3. Active

After deployment, the smart account is a live contract on-chain. Subsequent UserOperations omit factory/factoryData and execute directly against the deployed account.

Advantages Over EOA Wallets

Feature	EOA Wallet	embarkAI Smart Account
Key management	Single private key	MPC threshold signatures (no single point of failure)
Gas payment	Must hold native tokens	Paymaster can sponsor gas
Batch operations	One tx at a time	Multiple calls in a single UserOperation
Account recovery	Seed phrase only	Vault backup with password encryption
Custom validation	ECDSA only	Programmable signature verification
Deployment cost	Free (built-in)	Deferred to first transaction (counterfactual)

How embarkAI Implements AA

embarkAI combines Account Abstraction with MPC security:

Key generation uses the DKLS23 2-of-2 threshold protocol — no single party holds the full private key
Smart accounts are deployed via a deterministic factory contract per chain
Bundler infrastructure is fully managed — you interact only with the SDK
Gas sponsorship is opt-in via Paymaster configuration
Batch operations are supported natively through sendBatchUserOperation

Next Steps

MPC Security — Learn how threshold signatures protect your keys
Paymaster — Configure gas sponsorship for your users
Server Wallets — Create and manage wallets from your backend
Send Your First Transaction — Hands-on tutorial